Touch system, its touch device and input device, and its signal transmission method

ABSTRACT

A touch system has a touch device and an input device. The touch system executes a first mode and a second mode at different times. In the first mode, the touch device transmits a modulation signal to drive the touch electrodes and to be used as an uplink signal. The input device receives the modulation signal. In the second mode, the touch device receives the downlink signal from the input device. Thus, the touch device does not have to transmit the driving signal and the uplink signal at different times. Then the time is saved for the rest work periods so that every work periods get longer length of time.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of United States provisionalapplication filed on Oct. 24, 2018 and having application Ser. No.62/750,192, the entire contents of which are hereby incorporated hereinby reference.

This application claims the benefit of United States provisionalapplication filed on Jun. 20, 2019 and having application Ser. No.62/863,878, the entire contents of which are hereby incorporated hereinby reference. This application is based upon and claims priority under35 U.S.C. 119 from Taiwan Patent Application No. 108129026 filed on Aug.14, 2019, which is hereby specifically incorporated herein by thisreference thereto.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to a touch system, especially to a touchsystem with two-way communication touch device and input device.

2. Description of the Prior Arts

In the conventional touch system, the touch device and the input devicecooperate to allow the user to manipulate the touch device through thefinger or the input device. In the prior art, the input device can senda message in one-way or receive and send a message in two-way.

Taking a two-way stylus with a touch device as an example, the touchdevice executes the detection of the finger and of the two-way stylus ina time division manner. When executing finger detection, the touchdevice sends a driving signal to the electrode units, and then samplesthe electrode units to perform capacitive sensing to capture the touchinformation of the finger. When executing the detection of the two-waystylus, the touch device first transmits an uplink signal through theelectrode units, and then detects a downlink signal of the two-waystylus with the electrode units. When the two-way stylus receives theuplink signal, the two-way stylus returns the downlink signal tosynchronize with the touch device. Therefore, for the electrode unis,they must divide a frame into different working periods to respectivelydetect the finger and the two-way stylus. Since the time of a frame isfixed, the more working periods are divided and the shorter the timethat can be allocated for each working period. This results ininsufficient detection time, which in turn affects the user experience.

SUMMARY OF THE INVENTION

In view of the aforementioned shortcomings, the present invention isdirected to improve the signal transmission method of the prior art inorder to improve the user experience.

To achieve the aforementioned advantages, the present invention providesa signal transmission method for a touch system, wherein the touchsystem comprises an input device and a touch device having a touchoperation area, multiple first electrode units, multiple secondelectrode units and a control unit, and the method comprises steps of:

executing a first mode and a second mode in a time division manner bythe touch device:

in the first mode, providing a modulation signal to at least one of thefirst electrode units for being used as a driving signal and an uplinksignal transmitted to the input device; and

in the second mode, receiving a downlink signal from the input devicethrough the first and second electrode units.

In another aspect, the present invention provides a touch systemcomprising:

a touch device having

-   -   a touch operation area;    -   multiple first electrode units arranged under the touch        operation area;    -   multiple second electrode units arranged under the touch        operation area along different direction to the first electrode        units; and    -   a control unit electrically connecting to the first and second        electrode units; and

an input device having

-   -   a controller; and    -   an electrode assembly electrically connecting to the controller;

wherein the touch device executes a first mode and a second mode in atime division manner;

wherein in the first mode, providing a modulation signal to at least oneof the first electrode units for being used as a driving signal and anuplink signal transmitted to the input device; and

wherein in the second mode, the first and second electrode units receivea downlink signal from the input device.

In another aspect, the present invention provides a signal transmissionmethod for a touch device, wherein the touch device comprises a touchoperation area, multiple first electrode units, multiple secondelectrode units and a control unit, and the method comprising a step of:

executing a first mode by providing a modulation signal to at least oneof the first electrode units for being used as a driving signal and anuplink signal transmitted to an input device.

In another aspect, the present invention provides a touch devicecomprising:

a touch operation area;

multiple first electrode units arranged under the touch operation area;

multiple second electrode units arranged under the touch operation areaalong different direction to the first electrode units; and

a control unit electrically connecting to the first and second electrodeunits

wherein the touch device executes a first mode by providing a modulationsignal to at least one of the first electrode units for being used as adriving signal and an uplink signal transmitted to an input device.

Therefore, by using the modulation signal as a characteristic of thedriving signal and the uplink signal, the present invention does notneed to transmit the driving signal and the uplink signal in atime-sharing manner. Thus, the time is freed up for the rest of the workperiods, so that in different frames, each different work periods can beallocated more time to execute.

Other objectives, advantages and novel features of the invention willbecome more apparent from the following detailed description when takenin conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is an illustrative view of a first embodiment of a touch systemin accordance with the present invention;

FIG. 1B is a block diagram of partial elements of an input device of thetouch system in FIG. 1A;

FIG. 2A is an illustrative view of a second embodiment of a touch systemin accordance with the present invention;

FIG. 2B is a block diagram of partial elements of an input device of thetouch system in FIG. 2A;

FIG. 3 is an illustrative operational view of the touch system in FIG.1A, showing the codes of the modulation signals;

FIG. 4 is an illustrative operational view of a first embodiment of asignal transmission method in accordance with the present invention,showing frames for signal transmission;

FIG. 5 is an illustrative operational view of a second embodiment of asignal transmission method in accordance with the present invention,showing frames for signal transmission;

FIG. 6 is an illustrative operational view of a third embodiment of asignal transmission method in accordance with the present invention,showing frames for signal transmission;

FIG. 7 is an illustrative operational view of a fourth embodiment of asignal transmission method in accordance with the present invention,showing frames for signal transmission;

FIG. 8 is an illustrative operational view of a fifth embodiment of asignal transmission method in accordance with the present invention,showing frames for signal transmission;

FIG. 9 is an illustrative operational view of a sixth embodiment of asignal transmission method in accordance with the present invention,showing frames for signal transmission;

FIG. 10 is an illustrative operational view of a seventh embodiment of asignal transmission method in accordance with the present invention,showing frames for signal transmission;

FIG. 11 is an illustrative operational view of a eighth embodiment of asignal transmission method in accordance with the present invention,showing frames for signal transmission;

FIG. 12 is an illustrative operational view of a ninth embodiment of asignal transmission method in accordance with the present invention,showing different modulation signals transmitted;

FIG. 13 is an illustrative operational view of a tenth embodiment of asignal transmission method in accordance with the present invention,showing different modulation signals transmitted;

FIG. 14 is an illustrative operational view of a eleventh embodiment ofa signal transmission method in accordance with the present invention,showing different modulation signals transmitted; and

FIG. 15 is an illustrative operational view of a twelfth embodiment of asignal transmission method in accordance with the present invention,showing different modulation signals transmitted.

DETAILED DESCRIPTION OF THE EMBODIMENTS

With reference to FIG. 1A, a touch system in accordance with the presentinvention comprises a touch device 10 and an input device 20.

The touch device 10 comprises a touch operation area 11, multiple firstelectrode units 12, multiple second electrode units 13 and a controlunit 14. The first electrode units 12 and the second electrode units 13are arranged along different directions under the touch operation area11. The control unit 14 respectively connects electrically to the firstelectrode units 12 and the second electrode units 13.

With reference to FIGS. 1A and 1B, the input device 20 comprises acontroller 21 and an electrode assembly 22. The electrode assembly 22electrically connects to the controller 21. In this embodiment, theinput device 20 is a stylus, but not limited thereto. In one embodimentas shown in FIGS. 1A and 1B, the electrode assembly 22 includes atransmitting and receiving electrode unit 220. The transmitting andreceiving electrode unit 220 separately executes a sending operation ofa downlink signal and a receiving of the modulation signal in a timedivision manner. In another embodiment as shown in FIGS. 2A and 2B, theelectrode assembly 22A includes a third electrode unit 221A and a fourthelectrode unit 222A. The input device 20A transmits the downlink signalthrough the third electrode unit 221A, and receives the modulationsignal through the fourth electrode unit 222A.

The touch system executes two modes in a time division manner. In afirst mode, the touch device 10 drives the first electrode units 12 byusing the modulation signal as a driving signal. The modulation signalis also sent to the input device 20 through the first electrode units 12as an uplink signal. A sensing signal is received by the secondelectrode units 13, and the change of the capacitance is used to sensewhether a finger touches the touch operation area 11 and to know theposition or other sensing information of the finger. The input device 20receives the modulation signal from the touch device 10 by the electrodeassembly 22. In a second mode, the touch device 10 receives the downlinksignal from the input device 20 by the first electrode units 12 and thesecond electrode units 13, thereby obtaining the location or otherauxiliary information of the input device 20.

In one embodiment, all of the first electrode units 12 are driven by thesame modulation signal. However, in another embodiment, in order todistinguish different modulation signals transmitted by the differentfirst electrode units 12, the modulation signals transmitted by thefirst electrode units 12 respectively have different modulationcharacteristics but are orthogonal to each other. The differentmodulation characteristics described above are, for example, differentspreading codes, etc., but are not limited thereto. With reference toFIG. 3, the spreading code of the modulation signal transmitted by thefirst electrode unit T_(x_1) of the i^(th) row is Code_(N), thespreading code of the modulation signal transmitted by the firstelectrode unit T_(x_i−1) of the i−1^(th) row is Code_(N−1), thespreading code of the modulation signal transmitted by the firstelectrode unit T_(x_i−2) on the i−2^(th) line is Code_(N−2), the spreadcode of the modulation signal transmitted by the first electrode unitT_(x i+1) of the i+1^(th) line is Code_(N+1), and the spreading code ofthe modulation signal transmitted by the first electrode unit T_(x_1+2)of the i+2^(th) row is Code_(N+2). In one embodiment, the touch device10 drives the first electrode units 12 of a specific number of rows withthe modulation signals having different modulation characteristicsinstead of transmitting by all of the foregoing first electrode units12. For example, the modulation signals having different modulationcharacteristics are transmitted by the odd or the even of the firstelectrode units 12 on the touch device 10; or the modulation signalshaving different modulation characteristics are transmitted by the firstelectrode units 12 at intervals of two or more, and the remaining firstelectrode units 12 may be inactive. In this case, the first electrodeunits 12 that transmit the modulation signals may also cover most of thetouch operation area 11 so that the input device 20 receives themodulation signal as the uplink signal when approaching or contactingthe touch device 10. In addition, the different modulationcharacteristics may include, but are not limited to, on-off keying(00K), Manchester coding, and Square.

The signal transmission method of the touch system in accordance withthe present invention has the following various embodiments, but is notlimited thereto.

With reference to FIGS. 4, 1A and 1B, the touch device 10 executes thefirst mode and the second mode in sequence in a frame. After receivingthe modulation signal of the touch device 10, the input device 20 startsto send the downlink signal when the touch device 10 switches to thesecond mode. In the first mode, the touch device 10 drives the firstelectrode units 12 with the modulation signal S₁, and the modulationsignal S₁ serves as the driving signal S₁₁ and the uplink signal Sitsimultaneously. The second electrode units 13 receive the sensingsignal, and the transmitting and receiving electrode unit 210 of theinput device 20 receives the modulation signal S₁. In the second mode,the first electrode units 12 and the second electrode units 13 of thetouch device 10 are configured to receive the downlink signal S₂ sent bythe transmitting and receiving electrode unit 210 of the input device20. In this embodiment, the input device 20 does not approach or contactthe touch operation area 11 of the touch device 10 during the first halfof a frame P₁. When the end of the frame P₁ is reached, the input device20 approaches or contacts the touch operation area 11 of the touchdevice 10. However, at this time, the transmitting and receivingelectrode unit 210 of the input device 20 fails to receive themodulation signal S₁ again in time. Therefore, until the beginning of aframe P₂, the transmitting and receiving electrode unit 210 of the inputdevice 20 completely receives the modulation signal S₁ sent by the firstelectrode units 12 for the first time. The input device 20 then sendsthe downlink signal S₂ every time the touch device 10 enters the secondmode until the input device 20 is away from the touch device 10 and themodulation signal S₁ is not received. With reference to FIGS. 5, 2A and2B, the touch device 10 executes two times of the first mode and thesecond mode in sequence in a frame. After receiving the modulationsignal of the touch device 10, the input device 20A starts to send thedownlink signal when the touch device 10 switches to the second mode. Inthe first mode, the touch device 10 drives the first electrode units 12with the modulation signal S₁, and the modulation signal S₁ serves asthe driving signal S₁₁ and the uplink signal Sit simultaneously. Thesecond electrode units 13 receive the sensing signal. The fourthelectrode unit 212A of the input device 20A receives the modulationsignal S₁. In the second mode, the first electrode units 12 and thesecond electrode units 13 of the touch device 10 are configured toreceive the downlink signal S₂ sent by the third electrode unit 211A ofthe input device 20A. The fourth electrode unit 212A of the input device20A can continuously receive the signal or switch to off. In thisembodiment, the input device 20A does not approach or contact the touchoperation area 11 of the touch device 10 during the first half of theframe P₁. When the end of the frame P₁ is reached, the input device 20Aapproaches or contacts the touch operation area 11 of the touch device10. However, at this time, the fourth electrode unit 212A of the inputdevice 20A fails to receive the modulation signal S₁ again in time.Therefore, until the beginning of the frame P₂, the fourth electrodeunit 212A of the input device 20A completely receives the modulationsignal S₁ that the first electrode units 12 transmit for the first timein the frame P₂. The third electrode unit 211A of the input device 20Athen sends the downlink signal S₂ every time the touch device 10 entersthe second mode until the input device 20A is away from the touch device10 and the modulation signal S₁ is not received.

With reference to FIGS. 6, 1A and 1B, the input device 20 transmits abeacon message at fixed time intervals even tough the input device 20does not receive the modulation signal. In the first mode, the touchdevice 10 drives the first electrode units 12 with the modulation signalS₃, and the modulation signal S₃ serves as the driving signal S₃₁ andthe uplink signal S₃₂ simultaneously. The second electrode units 13receive the sensing signal, and the transmitting and receiving electrodeunit 210 of the input device 20 receives the modulation signal S₃. Inthe second mode, the first electrode units 12 and the second electrodeunits 13 of the touch device 10 are configured to receive the beaconmessage S₄ from the transmitting and receiving electrode unit 210 of theinput device 20. In this embodiment, when the input device 20 does notreceive the modulation signal S₃, the transmitting and receivingelectrode unit 210 of the input device 20 sends the beacon message S₄ atthe beginning of each frame, and then receives the signal. When thetransmitting and receiving electrode unit 210 of the input device 20receives the modulation signal S₃ sent by the first electrode units 11during the frame P_(x), the input device 20 interrupts the originalframe P_(x) in advance in response to the execution time of the nextsecond mode of the touch device 10. Then the input device 20 enters thenext frame P_(x+1). That is, the input device 20 interrupts the timethat should originally receives signals and starts transmitting thebeacon message S₄ corresponding to the start time of the second mode ofthe touch device 10. However, the input device 20 does not change thetime of sending and receiving signals in other subsequent frames exceptthe time of receiving the signal is shortened in the frame P. The inputdevice 20 starts transmitting the beacon message S₄ earlier tosynchronize the input device 20 with the touch device 10 in advance.Then the reaction speed between the input device 20 and the touch device10 is effectively improved.

With reference to FIGS. 7, 2A and 2B, the input device 20A transmits abeacon message at fixed time intervals even tough the input device 20Adoes not receive the modulation signal. In the first mode, the touchdevice 10 drives the first electrode units 12 with the modulation signalS₃, and the modulation signal S₃ serves as the driving signal S₃₁ andthe uplink signal S₃₂ simultaneously. The second electrode units 13receive the sensing signal, and the fourth electrode unit 212A of theinput device 20A receives the modulation signal S₃. In the second mode,the first electrode units 12 and the second electrode units 13 of thetouch device 10 are configured to receive the beacon message S₄ from thethird electrode unit 211A of the input device 20A. The fourth electrodeunit 212A of the input device 20A can continuously receive the signal orswitch to off. In this embodiment, when the input device 20A does notreceive the modulation signal S₃, the third electrode unit 211A of theinput device 20A sends the beacon message S₄ at the beginning of eachframe, and then the fourth electrode unit 212A of the input device 20Areceives the signal. When the fourth electrode unit 212A of the inputdevice 20A receives the modulation signal S₃ sent by the first electrodeunits 12 during the frame P_(x), the input device 20A interrupts theoriginal frame P_(x) in advance in response to the execution time of thenext second mode of the touch device 10. Then the input device 20Aenters the next frame P_(x+1). That is, the input device 20A interruptsthe time that should originally receives signals and starts transmittingthe beacon message S₄ corresponding to the start time of the second modeof the touch device 10. However, the input device 20 does not change thetime of other subsequent frames except shortening the time of the frameP. The input device 20A starts transmitting the beacon message S₄earlier to synchronize the input device 20A with the touch device 10 inadvance. Then the reaction speed between the input device 20A and thetouch device 10 is effectively improved.

With reference to FIGS. 8, 1A and 1B, the input device 20 transmits abeacon message at fixed time intervals and with a fixed length of timeeven tough the input device 20 does not receive the modulation signal.In the first mode, the touch device 10 drives the first electrode units12 with the modulation signal S₅, and the modulation signal S₅ serves asthe driving signal S₅₁ and the uplink signal S₅₂ simultaneously. Thesecond electrode units 13 receive the sensing signal, and thetransmitting and receiving electrode unit 210 of the input device 20receives the modulation signal S₅. In the second mode, the firstelectrode units 12 and the second electrode units 13 of the touch device10 are configured to receive the beacon message S₆₀, S₆₁ from thetransmitting and receiving electrode unit 210 of the input device 20. Inthis embodiment, when the input device 20 does not receive themodulation signal S₅, the transmitting and receiving electrode unit 210of the input device 20 sends the beacon message S₆₀ at the beginning ofeach frame, and then receives the signal. When the transmitting andreceiving electrode unit 210 of the input device 20 receives themodulation signal S₅ sent by the first electrode units 12 during theframe P_(y), the input device 20 interrupts the original frame P_(y) inadvance in response to the execution time of the next second mode of thetouch device 10. Then the input device 20 enters the next frame P_(y+1).That is, the input device 20 interrupts the time that should originallyreceives signals and starts transmitting the beacon message S₆₁corresponding to the start time of the second mode of the touch device10. The amount and or the time length of the beacon message S₆₁ is alsoincreased in the frame P_(y+1). However, the input device 20 does notchange the time of sending and receiving signals in other subsequentframes except the time of receiving the signal is shortened in the frameP_(y) and the amount and or the time length of the beacon message S₆₁ isincreased in the frame P_(y+1). The input device 20 starts transmittingthe beacon message S₆₁ earlier and increases the amount or the timelength of the beacon message S₆₁ to synchronize the input device 20 withthe touch device 10 in advance and obtain enough synchronizationinformation.

With reference to FIGS. 9, 2A and 2B, the input device 20A transmits abeacon message at fixed time intervals and with a fixed length of timeeven though the input device 20A does not receive the modulation signal.In the first mode, the touch device 10 drives the first electrode units12 with the modulation signal S₅, and the modulation signal S₅ serves asthe driving signal S₅₁ and the uplink signal S₅₂ simultaneously. Thesecond electrode units 13 receive the sensing signal, and the fourthelectrode unit 212A of the input device 20A receives the modulationsignal S₅. In the second mode, the first electrode units 12 and thesecond electrode units 13 of the touch device 10 are configured toreceive the beacon message S₆₀ from the third electrode unit 211A of theinput device 20A. The fourth electrode unit 212A of the input device 20Acan continuously receive the signal or switch to off. In thisembodiment, when the input device 20A does not receive the modulationsignal S₅, the third electrode unit 211A of the input device 20A sendsthe beacon message S₆₀ at the beginning of each frame, and then thefourth electrode unit 212A of the input device 20A receives the signal.When the fourth electrode unit 212A of the input device 20A receives themodulation signal S₅ sent by the first electrode units 12 during theframe P_(y), the input device 20A interrupts the original frame P_(y) inadvance in response to the execution time of the next second mode of thetouch device 10. Then the input device 20A enters the next frameP_(y+1). That is, the input device 20A interrupts the time that shouldoriginally receive signals, and starts transmitting the beacon messageS₆₁ corresponding to the start time of the second mode of the touchdevice 10. However, the input device 20A does not change the time ofsending and receiving signals in other subsequent frames except the timeof receiving the signal is shortened in the frame P_(y) and the amountand or the time length of the beacon message S₆₁ is increased in theframe P_(y+1). The input device 20A starts transmitting the beaconmessage S₆₁ earlier and increases the amount and or the time length ofthe beacon message S₆₁ to synchronize the input device 20A with thetouch device 10 in advance and obtain enough synchronizationinformation.

With reference to FIGS. 10, 1A and 1B, the input device 20 transmits abeacon message and a side information (recording information such aspressure information, battery information and so on of the input device20) at fixed time intervals even though the input device 20 does notreceive the modulation signal. In the first mode, the touch device 10drives the first electrode units 12 with the modulation signal S₇, andthe modulation signal S₇ serves as the driving signal S₇₁ and the uplinksignal S₇₂ simultaneously. The second electrode units 13 receive thesensing signal, and the transmitting and receiving electrode unit 210 ofthe input device 20 receives the modulation signal S₇. In the secondmode, the first electrode units 12 and the second electrode units 13 ofthe touch device 10 are configured to receive the beacon message S₈ andthe side information S₉ from the transmitting and receiving electrodeunit 210 of the input device 20. In this embodiment, when the inputdevice 20 does not receive the modulation signal S₇, the transmittingand receiving electrode unit 210 of the input device 20 sends the beaconmessage S₈ and the side information S₉ at the beginning of each frame,and then receives the signal. When the transmitting and receivingelectrode unit 210 of the input device 20 receives the modulation signalS₇ sent by the first electrode units 12 during the frame P_(z), theinput device 20 interrupts the original frame P_(z) in advance inresponse to the execution time of the next second mode of the touchdevice 10. Then the input device 20 enters the next frame P_(z+1). Thatis, the input device 20 interrupts the time that should originally beused to receive signals, and starts transmitting the beacon message S₈and the side information S₉ corresponding to the start time of thesecond mode of the touch device 10. However, the input device 20 doesnot change the time of sending and receiving signals in other subsequentframes except the time of receiving the signal is shortened in the frameP_(z). The input device 20 starts transmitting the beacon message S₈earlier to synchronize the input device 20 with the touch device 10 inadvance. Then the reaction speed between the input device 20 and thetouch device 10 is effectively improved. With reference to FIGS. 11, 2Aand 2B, the input device 20A transmits a beacon message and a sideinformation (recording information such as pressure information, batteryinformation and so on of the input device 20) at fixed time intervalseven though the input device 20A does not receive the modulation signal.In the first mode, the touch device 10 drives the first electrode units12 with the modulation signal S₇, and the modulation signal S₇ serves asthe driving signal S₇₁ and the uplink signal S₇₂ simultaneously. Thesecond electrode units 13 receive the sensing signal, and the fourthelectrode unit 212A of the input device 20A receives the modulationsignal S₇. In the second mode, the first electrode units 12 and thesecond electrode units 13 of the touch device 10 are configured toreceive the beacon message S₈ and the side information S₉ from the thirdelectrode unit 211A of the input device 20A. The fourth electrode unit212A of the input device 20A can continuously receive the signal orswitch to off. In this embodiment, when the input device 20A does notreceive the modulation signal S₇, the third electrode unit 211A of theinput device 20A sends the beacon message S₈ and the side information S₉at the beginning of each frame, and then the fourth electrode unit 212Aof the input device 20A receives the signal. When the fourth electrodeunit 212A of the input device 20A receives the modulation signal S₇ sentby the first electrode units 12 during the frame P_(z), the input device20A interrupts the original frame P_(z) in advance in response to theexecution time of the next second mode of the touch device 10. Then theinput device 20A enters the next frame P_(z+1). That is, the inputdevice 20A interrupts the time that should originally receives signalsand starts transmitting the beacon message S₈ and the side informationS₉ corresponding to the start time of the second mode of the touchdevice 10. However, the input device 20 does not change the time ofother subsequent frames except shortening the time of the frame P_(z).The input device 20A starts transmitting the beacon message S₈ and theside information S₉ earlier to synchronize the input device 20A with thetouch device 10 in advance. Then the reaction speed between the inputdevice 20A and the touch device 10 is effectively improved.

In addition, in one embodiment, the input device 20A enters the nextframe P_(z+1) as a synchronization frame when the fourth electrode unit212A of the input device 20A receives the modulation signal S₇ sent bythe first electrode units 12 during the frame P. A time period or afrequency of sending the beacon message by the input device 20A duringthe synchronization frame P_(z+1) is greater than a time period or afrequency of sending the beacon message by the input device during theoriginal frame P.

Further, in one embodiment, when the touch device 10 has not receivedthe beacon message from the input device 20, the modulation signaltransmitted by the touch device 10 in the first mode has a modulationcharacteristic A. When the touch device 10 has received the beaconmessage from the input device 20, the modulation signal transmitted bythe touch device 10 in the first mode has a modulation characteristic B.The modulation characteristic A and the modulation characteristic B aredifferent modulation characteristics. Thereby, the input device 20 thathas been synchronized with the touch device 10 no longer receives themodulation signal with the modulation characteristic A and synchronizesagain.

In another aspect, the noise interference may be occurred when the inputdevice 20 is used on the touch device 10. For example, when the inputdevice 20 is hand-held, the palm portion of the user accidentallytouches other parts of the touch operation area 11, and the uplinksignal sent by the parts is coupled to the input device 20 through thepalm portion of the user. In view of the above, the touch device 10transmits the original modulation signal via the first electrode unit 12to the area of the touch operation area 11 adjacent to where the inputdevice 20 hovers over or contacts when the touch device 10 detects theinput device 20. In other areas, an auxiliary signal is sent instead, soas to effectively eliminate noise interference.

With reference to FIGS. 12 and 1A, when the input device 20 hovers overor contacts the touch device 10, the touch device 10 determines thehovering or contact position O based on the downlink signal of the inputdevice 20. Then the area adjacent to the position O on the touchoperation area 11 is a first area 111, and the remaining area is asecond area 112. In the first mode, the touch device 10 transmits themodulation signal through the first electrode units 12 in the first area111, wherein all or part of the first electrode units 12 in the firstarea 111 transmits the modulation signal. The modulation signals may allhave the same modulation characteristics or have different modulationcharacteristics but are orthogonal to each other. For the second area112, the touch device 10 transmits the auxiliary signal through thefirst electrode units 12 of all or part of the second area 112. Theauxiliary signal is a ground signal, wherein the ground signal refers toproviding a fixed potential to the first electrode units 12 or groundingthe first electrode units 12.

With reference to FIGS. 13 and 1A, when the input device 20 hovers overor contacts the touch device 10, the touch device 10 determines thehovering or contact position P based on the downlink signal of the inputdevice 20. Then the area adjacent to the position P on the touchoperation area 11 is a first area 111, and the remaining area is asecond area 112. In the first mode, the touch device 10 transmits themodulation signal with a first spreading code or a first coding waythrough the first electrode units 12 in the first area 111, wherein allor part of the first electrode units 12 in the first area 111 transmitsthe modulation signal. The modulation signals may all have the samemodulation characteristics or have different modulation characteristicsbut are orthogonal to each other. For the second area 112, the touchdevice 10 transmits the auxiliary signal with a second spreading code ora second coding way through the first electrode units 12 of all or partof the second area 112. With reference to FIGS. 14 and 1A, when theinput device 20 hovers over or contacts the touch device 10, the touchdevice 10 determines the hovering or contact position Q based on thedownlink signal of the input device 20. Then the area adjacent to theposition Q on the touch operation area 11 is a first area 111, and theremaining area is a second area 112. In the first mode, the touch device10 transmits the modulation signal with a sine wave through the firstelectrode units 12 in the first area 111, wherein all or part of thefirst electrode units 12 in the first area 111 transmits the modulationsignal. The modulation signals may all have the same modulationcharacteristics or have different modulation characteristics but areorthogonal to each other. For the second area 112, the touch device 10transmits the auxiliary signal with a square wave through the firstelectrode units 12 of all or part of the second area 112. In anotherembodiment, before the touch device 10 receives the downlink signal fromthe input device 20, the touch device 10 transmits a mixed modulationsignal having two different waveforms or different modulationcharacteristics through the first electrode unit 12, such as a mixedmodulation signal with a sine wave and a square wave. After receivingthe downlink signal, the touch device 10 transmits a modulation signalwith one of the waveforms (such as a sine wave) or one of the modulationcharacteristics through the first electrode unit 12 in the first region111, and transmits a modulation signal with another waveform (such as asquare wave) or another modulation characteristic through the firstelectrode unit 12 in the second area 112.

Even though numerous characteristics and advantages of the presentinvention have been set forth in the foregoing description, togetherwith details of the structure and features of the invention, thedisclosure is illustrative only. Changes may be made in the details,especially in matters of shape, size, and arrangement of parts withinthe principles of the invention to the full extent indicated by thebroad general meaning of the terms in which the appended claims areexpressed.

What is claimed is:
 1. A signal transmission method for a touch system,wherein the touch system comprises an input device and a touch devicehaving a touch operation area, multiple first electrode units, multiplesecond electrode units and a control unit, and the method comprisessteps of: executing a first mode and a second mode in a time divisionmanner by the touch device: in the first mode, providing a modulationsignal to at least one of the first electrode units for being used as adriving signal and an uplink signal transmitted to the input device; andin the second mode, receiving a downlink signal from the input devicethrough the first and second electrode units.
 2. The signal transmissionmethod for a touch system as claimed in claim 1, wherein the touchdevice provides the modulation signals to two of the first electrodeunits in the first mode; the modulation signal provided to one of thetwo of the first electrode units has a first modulation characteristic;the modulation signal provided to another one of the two of the firstelectrode units has a second modulation characteristic; and the firstand second modulation characteristics are different but are orthogonalto each other.
 3. The signal transmission method for a touch system asclaimed in claim 2, wherein the two of the first electrode units areadjacent or spaced apart from each other by n rows of the firstelectrode units, and n is greater than or equal to
 1. 4. The signaltransmission method for a touch system as claimed in claim 1, whereinthe control unit of the touch device divides the touch operation area ofthe touch device into a first area and a second area according to aposition of the input device when the touch device receives the downlinksignal from the input device; the first area is an area where the inputdevice hovers over or contacts the touch device; the second area isanother area other than the first area, the first electrode units in thefirst area are driven by the modulation signal in subsequent first mode;the first electrode units in the second area are driven by an auxiliarysignal in subsequent first mode; and the modulation signal is differentto the auxiliary signal.
 5. The signal transmission method for a touchsystem as claimed in claim 4, wherein the auxiliary signal is a signalwith a constant potential.
 6. The signal transmission method for a touchsystem as claimed in claim 4, wherein the modulation signal and theauxiliary signal have different waveforms, different spreading codes,different coding ways or different phases.
 7. The signal transmissionmethod for a touch system as claimed in claim 1, wherein the inputdevice transmits a beacon message at predetermined time intervals; theinput device ends an original frame and then enters a synchronizationframe when the input device receives the modulation signal sent by thetouch device; and then the input device sends the beacon message duringthe synchronization frame.
 8. The signal transmission method for a touchsystem as claimed in claim 7, wherein a time period or a frequency ofsending the beacon message by the input device during thesynchronization frame is greater than a time period or a frequency ofsending the beacon message by the input device during the originalframe.
 9. The signal transmission method for a touch system as claimedin claim 7, wherein the modulation signal sent by the touch device inthe first mode has a third modulation characteristic when the touchdevice does not receive the beacon message from the input device; themodulation signal sent by the touch device in the subsequent first modehas a fourth modulation characteristic when the touch device receive thebeacon message from the input device; and the first and secondmodulation characteristics are different.
 10. The signal transmissionmethod for a touch system as claimed in claim 9, wherein the first andsecond modulation characteristics being different means that the firstand second modulation characteristics have different spreading codes orare coded in different ways.
 11. A touch system comprising: a touchdevice having a touch operation area; multiple first electrode unitsarranged under the touch operation area; multiple second electrode unitsarranged under the touch operation area along different direction to thefirst electrode units; and a control unit electrically connecting to thefirst and second electrode units; and an input device having; acontroller; and an electrode assembly electrically connecting to thecontroller; wherein the touch device executes a first mode and a secondmode in a time division manner; wherein in the first mode, providing amodulation signal to at least one of the first electrode units for beingused as a driving signal and an uplink signal transmitted to the inputdevice; and wherein in the second mode, the first and second electrodeunits receive a downlink signal from the input device.
 12. The touchsystem as claimed in claim 11, wherein the electrode assembly has atransmitting and receiving electrode unit and separately executes asending operation of the downlink signal and a receiving operation ofthe modulation signal in a time division manner.
 13. The touch system asclaimed in claim 11, wherein the electrode assembly has a thirdelectrode unit and a fourth electrode unit; the input device transmitsthe downlink signal through the third electrode unit, and receives themodulation signal through the fourth electrode unit.
 14. The touchsystem as claimed in claim 11, wherein the touch device provides themodulation signals to two of the first electrode units in the firstmode; the modulation signal provided to one of the two of the firstelectrode units has a first modulation characteristic; the modulationsignal provided to another one of the two of the first electrode unitshas a second modulation characteristic; and the first and secondmodulation characteristics are different but are orthogonal to eachother.
 15. A signal transmission method for a touch device, wherein thetouch device comprises a touch operation area, multiple first electrodeunits, multiple second electrode units and a control unit, and themethod comprising a step of: executing a first mode by providing amodulation signal to at least one of the first electrode units for beingused as a driving signal and an uplink signal transmitted to an inputdevice.
 16. The signal transmission method for a touch device as claimedin claim 15, wherein the touch device provides the modulation signals totwo of the first electrode units in the first mode; the modulationsignal provided to one of the of the first electrode units has a firstmodulation characteristic; the modulation signal provided to another oneof the two of the first electrode units has a second modulationcharacteristic; and the first and second modulation characteristics aredifferent but are orthogonal to each other.
 17. The signal transmissionmethod for a touch device as claimed in claim 16, wherein the two of thefirst electrode units are adjacent or spaced apart from each other by nrows of the first electrode units, and n is greater than or equal to 1.18. The signal transmission method for a touch device as claimed inclaim 15 further comprising a step of executing a second mode byproceeding capacitive sensing through the first electrode units and thesecond electrode units simultaneously, wherein the first mode and thesecond mode are executed in a time division manner; the control unit ofthe touch device divides the touch operation area of the touch deviceinto a first area and a second area according to a position of the inputdevice when the touch device receives the downlink signal from the inputdevice; the first area is an area where the input device hovers over orcontacts the touch device; the second area is another area other thanthe first area, the first electrode units in the first area are drivenby the modulation signal in subsequent first mode; the first electrodeunits in the second area are driven by an auxiliary signal in subsequentfirst mode; and the modulation signal is different to the auxiliarysignal.
 19. The signal transmission method for a touch device as claimedin claim 18, wherein the auxiliary signal is a signal with a constantpotential.
 20. The signal transmission method for a touch device asclaimed in claim 18, wherein the modulation signal and the auxiliarysignal have different waveforms, different spreading codes, differentcoding ways or different phases.
 21. A touch device comprising: a touchoperation area; multiple first electrode units arranged under the touchoperation area; multiple second electrode units arranged under the touchoperation area along different direction to the first electrode units;and a control unit electrically connecting to the first and secondelectrode units wherein the touch device executes a first mode byproviding a modulation signal to at least one of the first electrodeunits for being used as a driving signal and an uplink signaltransmitted to an input device.
 22. The touch device as claimed in claim21, wherein the touch device provides the modulation signals to two ofthe first electrode units in the first mode; the modulation signalprovide to one of the two of the first electrode units has a firstmodulation characteristic; the modulation signal provided to another oneof the two of the first electrode units has a second modulationcharacteristic; and the first and second modulation characteristics aredifferent but are orthogonal to each other.